Melphalan, also known as L-phenylalanine mustard, L-PAM, or L-sarcolysin is a phenylalanine derivative of nitrogen mustard. Melphalan is a bifunctional alkylating agent that is active against selected human neoplastic diseases. The molecular formula is C13H18Cl2N2O2 and the molecular weight is 305.20. The structural formula is:

U.S. Pat. No. 4,997,651 to Stephen et al., discloses two-component pharmaceutical formulation of Melphalan comprising freeze-dried Melphalan hydrochloride and a solvent-diluent comprising a citrate, propylene glycol and ethanol.
U.S patent application No. 2013/0131174 to Castillo et al., discloses a solid lyophilized composition of Melphalan hydrochloride having a pH between 4 and 6.
U.S patent application Nos. 2010/0311838, 2014/0213650 and 2014/0221488 disclose parenteral compositions comprising Melphalan and a cyclodextrin derivative.
RU2060031 discloses parenteral lyophilized formulation comprising a Melphalan, polyvinylpyrrolidone, ascorbic acid, glutamic acid, hydrochloric acid and D-mannitol.
The commercial formulation of injectable Alkeran® consists of two components comprising of Melphalan hydrochloride and polyvinylpyrrolidone lyophilized and a diluent comprising a mixture of sodium citrate, water for injection, propylene glycol and ethanol.
The Alkeran® to be infused must be diluted to not more than 0.45 mg/ml in normal saline and infused over 15 minutes.
The reconstitution of the lyophilized product is clinically inconvenient and the lyophilization process is time consuming and often incurs significant expense. Hence, there is a strong need to develop alternate formulations of Melphalan.
The inventors have developed ready to use liquid formulation of Melphalan which overcomes the disadvantages of the formulations reported in prior art.